1. Field of the Invention
The present invention relates to an ink supplying system such as an ink cartridge, a connection unit, etc., for supplying ink to an ink jet recording head that ejects ink droplets in response to a print signal. The present invention also relates to a recording apparatus using such an ink supplying system.
2. Related Art
In a recording apparatus of the type in which ink is supplied to an ink jet recording head from an ink cartridge that is detachably mounted on a carriage having the recording head thereon, the cartridge is constructed such that the ink is filled in a flexible ink bag and the ink bag is accommodated in a hard case as disclosed, for example, in Europe Patent No. 562717.
Since the ink cartridge thus constructed has no porous member, the ink cartridge can efficiently utilize the container volume of the ink cartridge to accommodate a large quantity of ink, thereby improving the ratio of the ink quantity per the container volume in comparison to an ink cartridge having the ink impregnated in a porous member.
However, since the ink is not held under a capillary force of the porous member, a liquid column of the accommodated ink directly acts on the recording head to change the ink pressure on the recording head depending on a change in quantity of ink. Further, pressure fluctuation acts on the recording head, which is caused by motion of the ink due to the reciprocal movement of the carriage. Consequently, the print quality is degraded.